US9005531B2 - Air decontamination device and method - Google Patents

Air decontamination device and method Download PDF

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Publication number
US9005531B2
US9005531B2 US13/259,815 US201013259815A US9005531B2 US 9005531 B2 US9005531 B2 US 9005531B2 US 201013259815 A US201013259815 A US 201013259815A US 9005531 B2 US9005531 B2 US 9005531B2
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air
housing
cathode
emitting device
thermal plasma
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US20120093691A1 (en
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Alan Mole
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Tri Air Developments Ltd
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Tri Air Developments Ltd
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    • AHUMAN NECESSITIES
    • A61MEDICAL OR VETERINARY SCIENCE; HYGIENE
    • A61LMETHODS OR APPARATUS FOR STERILISING MATERIALS OR OBJECTS IN GENERAL; DISINFECTION, STERILISATION OR DEODORISATION OF AIR; CHEMICAL ASPECTS OF BANDAGES, DRESSINGS, ABSORBENT PADS OR SURGICAL ARTICLES; MATERIALS FOR BANDAGES, DRESSINGS, ABSORBENT PADS OR SURGICAL ARTICLES
    • A61L9/00Disinfection, sterilisation or deodorisation of air
    • A61L9/16Disinfection, sterilisation or deodorisation of air using physical phenomena
    • A61L9/22Ionisation
    • AHUMAN NECESSITIES
    • A61MEDICAL OR VETERINARY SCIENCE; HYGIENE
    • A61LMETHODS OR APPARATUS FOR STERILISING MATERIALS OR OBJECTS IN GENERAL; DISINFECTION, STERILISATION OR DEODORISATION OF AIR; CHEMICAL ASPECTS OF BANDAGES, DRESSINGS, ABSORBENT PADS OR SURGICAL ARTICLES; MATERIALS FOR BANDAGES, DRESSINGS, ABSORBENT PADS OR SURGICAL ARTICLES
    • A61L2/00Methods or apparatus for disinfecting or sterilising materials or objects other than foodstuffs or contact lenses; Accessories therefor
    • A61L2/02Methods or apparatus for disinfecting or sterilising materials or objects other than foodstuffs or contact lenses; Accessories therefor using physical phenomena
    • A61L2/14Plasma, i.e. ionised gases
    • AHUMAN NECESSITIES
    • A61MEDICAL OR VETERINARY SCIENCE; HYGIENE
    • A61LMETHODS OR APPARATUS FOR STERILISING MATERIALS OR OBJECTS IN GENERAL; DISINFECTION, STERILISATION OR DEODORISATION OF AIR; CHEMICAL ASPECTS OF BANDAGES, DRESSINGS, ABSORBENT PADS OR SURGICAL ARTICLES; MATERIALS FOR BANDAGES, DRESSINGS, ABSORBENT PADS OR SURGICAL ARTICLES
    • A61L9/00Disinfection, sterilisation or deodorisation of air
    • A61L9/015Disinfection, sterilisation or deodorisation of air using gaseous or vaporous substances, e.g. ozone
    • AHUMAN NECESSITIES
    • A61MEDICAL OR VETERINARY SCIENCE; HYGIENE
    • A61LMETHODS OR APPARATUS FOR STERILISING MATERIALS OR OBJECTS IN GENERAL; DISINFECTION, STERILISATION OR DEODORISATION OF AIR; CHEMICAL ASPECTS OF BANDAGES, DRESSINGS, ABSORBENT PADS OR SURGICAL ARTICLES; MATERIALS FOR BANDAGES, DRESSINGS, ABSORBENT PADS OR SURGICAL ARTICLES
    • A61L9/00Disinfection, sterilisation or deodorisation of air
    • A61L9/16Disinfection, sterilisation or deodorisation of air using physical phenomena
    • A61L9/18Radiation
    • A61L9/20Ultraviolet radiation
    • BPERFORMING OPERATIONS; TRANSPORTING
    • B01PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
    • B01DSEPARATION
    • B01D53/00Separation of gases or vapours; Recovering vapours of volatile solvents from gases; Chemical or biological purification of waste gases, e.g. engine exhaust gases, smoke, fumes, flue gases, aerosols
    • B01D53/32Separation of gases or vapours; Recovering vapours of volatile solvents from gases; Chemical or biological purification of waste gases, e.g. engine exhaust gases, smoke, fumes, flue gases, aerosols by electrical effects other than those provided for in group B01D61/00
    • BPERFORMING OPERATIONS; TRANSPORTING
    • B01PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
    • B01DSEPARATION
    • B01D53/00Separation of gases or vapours; Recovering vapours of volatile solvents from gases; Chemical or biological purification of waste gases, e.g. engine exhaust gases, smoke, fumes, flue gases, aerosols
    • B01D53/32Separation of gases or vapours; Recovering vapours of volatile solvents from gases; Chemical or biological purification of waste gases, e.g. engine exhaust gases, smoke, fumes, flue gases, aerosols by electrical effects other than those provided for in group B01D61/00
    • B01D53/323Separation of gases or vapours; Recovering vapours of volatile solvents from gases; Chemical or biological purification of waste gases, e.g. engine exhaust gases, smoke, fumes, flue gases, aerosols by electrical effects other than those provided for in group B01D61/00 by electrostatic effects or by high-voltage electric fields
    • BPERFORMING OPERATIONS; TRANSPORTING
    • B01PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
    • B01DSEPARATION
    • B01D53/00Separation of gases or vapours; Recovering vapours of volatile solvents from gases; Chemical or biological purification of waste gases, e.g. engine exhaust gases, smoke, fumes, flue gases, aerosols
    • B01D53/34Chemical or biological purification of waste gases
    • B01D53/74General processes for purification of waste gases; Apparatus or devices specially adapted therefor
    • B01D53/86Catalytic processes
    • B01D53/88Handling or mounting catalysts
    • B01D53/885Devices in general for catalytic purification of waste gases
    • BPERFORMING OPERATIONS; TRANSPORTING
    • B03SEPARATION OF SOLID MATERIALS USING LIQUIDS OR USING PNEUMATIC TABLES OR JIGS; MAGNETIC OR ELECTROSTATIC SEPARATION OF SOLID MATERIALS FROM SOLID MATERIALS OR FLUIDS; SEPARATION BY HIGH-VOLTAGE ELECTRIC FIELDS
    • B03CMAGNETIC OR ELECTROSTATIC SEPARATION OF SOLID MATERIALS FROM SOLID MATERIALS OR FLUIDS; SEPARATION BY HIGH-VOLTAGE ELECTRIC FIELDS
    • B03C3/00Separating dispersed particles from gases or vapour, e.g. air, by electrostatic effect
    • B03C3/01Pretreatment of the gases prior to electrostatic precipitation
    • B03C3/016Pretreatment of the gases prior to electrostatic precipitation by acoustic or electromagnetic energy, e.g. ultraviolet light
    • BPERFORMING OPERATIONS; TRANSPORTING
    • B03SEPARATION OF SOLID MATERIALS USING LIQUIDS OR USING PNEUMATIC TABLES OR JIGS; MAGNETIC OR ELECTROSTATIC SEPARATION OF SOLID MATERIALS FROM SOLID MATERIALS OR FLUIDS; SEPARATION BY HIGH-VOLTAGE ELECTRIC FIELDS
    • B03CMAGNETIC OR ELECTROSTATIC SEPARATION OF SOLID MATERIALS FROM SOLID MATERIALS OR FLUIDS; SEPARATION BY HIGH-VOLTAGE ELECTRIC FIELDS
    • B03C3/00Separating dispersed particles from gases or vapour, e.g. air, by electrostatic effect
    • B03C3/02Plant or installations having external electricity supply
    • B03C3/04Plant or installations having external electricity supply dry type
    • B03C3/09Plant or installations having external electricity supply dry type characterised by presence of stationary flat electrodes arranged with their flat surfaces at right angles to the gas stream
    • BPERFORMING OPERATIONS; TRANSPORTING
    • B03SEPARATION OF SOLID MATERIALS USING LIQUIDS OR USING PNEUMATIC TABLES OR JIGS; MAGNETIC OR ELECTROSTATIC SEPARATION OF SOLID MATERIALS FROM SOLID MATERIALS OR FLUIDS; SEPARATION BY HIGH-VOLTAGE ELECTRIC FIELDS
    • B03CMAGNETIC OR ELECTROSTATIC SEPARATION OF SOLID MATERIALS FROM SOLID MATERIALS OR FLUIDS; SEPARATION BY HIGH-VOLTAGE ELECTRIC FIELDS
    • B03C3/00Separating dispersed particles from gases or vapour, e.g. air, by electrostatic effect
    • B03C3/02Plant or installations having external electricity supply
    • B03C3/16Plant or installations having external electricity supply wet type
    • BPERFORMING OPERATIONS; TRANSPORTING
    • B03SEPARATION OF SOLID MATERIALS USING LIQUIDS OR USING PNEUMATIC TABLES OR JIGS; MAGNETIC OR ELECTROSTATIC SEPARATION OF SOLID MATERIALS FROM SOLID MATERIALS OR FLUIDS; SEPARATION BY HIGH-VOLTAGE ELECTRIC FIELDS
    • B03CMAGNETIC OR ELECTROSTATIC SEPARATION OF SOLID MATERIALS FROM SOLID MATERIALS OR FLUIDS; SEPARATION BY HIGH-VOLTAGE ELECTRIC FIELDS
    • B03C3/00Separating dispersed particles from gases or vapour, e.g. air, by electrostatic effect
    • B03C3/34Constructional details or accessories or operation thereof
    • B03C3/36Controlling flow of gases or vapour
    • B03C3/361Controlling flow of gases or vapour by static mechanical means, e.g. deflector
    • B03C3/366Controlling flow of gases or vapour by static mechanical means, e.g. deflector located in the filter, e.g. special shape of the electrodes
    • BPERFORMING OPERATIONS; TRANSPORTING
    • B03SEPARATION OF SOLID MATERIALS USING LIQUIDS OR USING PNEUMATIC TABLES OR JIGS; MAGNETIC OR ELECTROSTATIC SEPARATION OF SOLID MATERIALS FROM SOLID MATERIALS OR FLUIDS; SEPARATION BY HIGH-VOLTAGE ELECTRIC FIELDS
    • B03CMAGNETIC OR ELECTROSTATIC SEPARATION OF SOLID MATERIALS FROM SOLID MATERIALS OR FLUIDS; SEPARATION BY HIGH-VOLTAGE ELECTRIC FIELDS
    • B03C3/00Separating dispersed particles from gases or vapour, e.g. air, by electrostatic effect
    • B03C3/34Constructional details or accessories or operation thereof
    • B03C3/40Electrode constructions
    • B03C3/60Use of special materials other than liquids
    • B03C3/64Use of special materials other than liquids synthetic resins
    • FMECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F24HEATING; RANGES; VENTILATING
    • F24FAIR-CONDITIONING; AIR-HUMIDIFICATION; VENTILATION; USE OF AIR CURRENTS FOR SCREENING
    • F24F3/00Air-conditioning systems in which conditioned primary air is supplied from one or more central stations to distributing units in the rooms or spaces where it may receive secondary treatment; Apparatus specially designed for such systems
    • F24F3/12Air-conditioning systems in which conditioned primary air is supplied from one or more central stations to distributing units in the rooms or spaces where it may receive secondary treatment; Apparatus specially designed for such systems characterised by the treatment of the air otherwise than by heating and cooling
    • F24F3/16Air-conditioning systems in which conditioned primary air is supplied from one or more central stations to distributing units in the rooms or spaces where it may receive secondary treatment; Apparatus specially designed for such systems characterised by the treatment of the air otherwise than by heating and cooling by purification, e.g. by filtering; by sterilisation; by ozonisation
    • FMECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F24HEATING; RANGES; VENTILATING
    • F24FAIR-CONDITIONING; AIR-HUMIDIFICATION; VENTILATION; USE OF AIR CURRENTS FOR SCREENING
    • F24F8/00Treatment, e.g. purification, of air supplied to human living or working spaces otherwise than by heating, cooling, humidifying or drying
    • F24F8/20Treatment, e.g. purification, of air supplied to human living or working spaces otherwise than by heating, cooling, humidifying or drying by sterilisation
    • F24F8/22Treatment, e.g. purification, of air supplied to human living or working spaces otherwise than by heating, cooling, humidifying or drying by sterilisation using UV light
    • FMECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F24HEATING; RANGES; VENTILATING
    • F24FAIR-CONDITIONING; AIR-HUMIDIFICATION; VENTILATION; USE OF AIR CURRENTS FOR SCREENING
    • F24F8/00Treatment, e.g. purification, of air supplied to human living or working spaces otherwise than by heating, cooling, humidifying or drying
    • F24F8/30Treatment, e.g. purification, of air supplied to human living or working spaces otherwise than by heating, cooling, humidifying or drying by ionisation
    • FMECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F24HEATING; RANGES; VENTILATING
    • F24FAIR-CONDITIONING; AIR-HUMIDIFICATION; VENTILATION; USE OF AIR CURRENTS FOR SCREENING
    • F24F8/00Treatment, e.g. purification, of air supplied to human living or working spaces otherwise than by heating, cooling, humidifying or drying
    • F24F8/80Self-contained air purifiers
    • HELECTRICITY
    • H01ELECTRIC ELEMENTS
    • H01JELECTRIC DISCHARGE TUBES OR DISCHARGE LAMPS
    • H01J37/00Discharge tubes with provision for introducing objects or material to be exposed to the discharge, e.g. for the purpose of examination or processing thereof
    • H01J37/32Gas-filled discharge tubes
    • HELECTRICITY
    • H05ELECTRIC TECHNIQUES NOT OTHERWISE PROVIDED FOR
    • H05HPLASMA TECHNIQUE; PRODUCTION OF ACCELERATED ELECTRICALLY-CHARGED PARTICLES OR OF NEUTRONS; PRODUCTION OR ACCELERATION OF NEUTRAL MOLECULAR OR ATOMIC BEAMS
    • H05H1/00Generating plasma; Handling plasma
    • H05H1/24Generating plasma
    • HELECTRICITY
    • H05ELECTRIC TECHNIQUES NOT OTHERWISE PROVIDED FOR
    • H05HPLASMA TECHNIQUE; PRODUCTION OF ACCELERATED ELECTRICALLY-CHARGED PARTICLES OR OF NEUTRONS; PRODUCTION OR ACCELERATION OF NEUTRAL MOLECULAR OR ATOMIC BEAMS
    • H05H1/00Generating plasma; Handling plasma
    • H05H1/24Generating plasma
    • H05H1/2406Generating plasma using dielectric barrier discharges, i.e. with a dielectric interposed between the electrodes
    • H05H1/2418Generating plasma using dielectric barrier discharges, i.e. with a dielectric interposed between the electrodes the electrodes being embedded in the dielectric
    • BPERFORMING OPERATIONS; TRANSPORTING
    • B01PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
    • B01DSEPARATION
    • B01D2255/00Catalysts
    • B01D2255/80Type of catalytic reaction
    • B01D2255/802Photocatalytic
    • BPERFORMING OPERATIONS; TRANSPORTING
    • B01PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
    • B01DSEPARATION
    • B01D2257/00Components to be removed
    • B01D2257/10Single element gases other than halogens
    • B01D2257/106Ozone
    • BPERFORMING OPERATIONS; TRANSPORTING
    • B01PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
    • B01DSEPARATION
    • B01D2257/00Components to be removed
    • B01D2257/90Odorous compounds not provided for in groups B01D2257/00 - B01D2257/708
    • BPERFORMING OPERATIONS; TRANSPORTING
    • B01PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
    • B01DSEPARATION
    • B01D2257/00Components to be removed
    • B01D2257/91Bacteria; Microorganisms
    • BPERFORMING OPERATIONS; TRANSPORTING
    • B01PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
    • B01DSEPARATION
    • B01D2259/00Type of treatment
    • B01D2259/45Gas separation or purification devices adapted for specific applications
    • B01D2259/4508Gas separation or purification devices adapted for specific applications for cleaning air in buildings
    • BPERFORMING OPERATIONS; TRANSPORTING
    • B01PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
    • B01DSEPARATION
    • B01D2259/00Type of treatment
    • B01D2259/80Employing electric, magnetic, electromagnetic or wave energy, or particle radiation
    • B01D2259/804UV light
    • BPERFORMING OPERATIONS; TRANSPORTING
    • B01PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
    • B01DSEPARATION
    • B01D2259/00Type of treatment
    • B01D2259/80Employing electric, magnetic, electromagnetic or wave energy, or particle radiation
    • B01D2259/806Microwaves
    • F24F2003/1667
    • F24F2003/1682
    • HELECTRICITY
    • H05ELECTRIC TECHNIQUES NOT OTHERWISE PROVIDED FOR
    • H05HPLASMA TECHNIQUE; PRODUCTION OF ACCELERATED ELECTRICALLY-CHARGED PARTICLES OR OF NEUTRONS; PRODUCTION OR ACCELERATION OF NEUTRAL MOLECULAR OR ATOMIC BEAMS
    • H05H1/00Generating plasma; Handling plasma
    • H05H1/24Generating plasma
    • H05H1/2406Generating plasma using dielectric barrier discharges, i.e. with a dielectric interposed between the electrodes
    • H05H1/2431Generating plasma using dielectric barrier discharges, i.e. with a dielectric interposed between the electrodes using cylindrical electrodes, e.g. rotary drums
    • HELECTRICITY
    • H05ELECTRIC TECHNIQUES NOT OTHERWISE PROVIDED FOR
    • H05HPLASMA TECHNIQUE; PRODUCTION OF ACCELERATED ELECTRICALLY-CHARGED PARTICLES OR OF NEUTRONS; PRODUCTION OR ACCELERATION OF NEUTRAL MOLECULAR OR ATOMIC BEAMS
    • H05H2245/00Applications of plasma devices
    • H05H2245/10Treatment of gases
    • H05H2245/15Ambient air; Ozonisers

Definitions

  • the present invention relates to an improved device for the decontamination of air and surfaces.
  • Air purity and being able to consistently remove contaminants entrained in the air is extremely important, especially in supposedly sterile or hygienic environments, such as hospitals and kitchens. It is also beneficial having decontaminated air in doctors' surgeries, and workplace environments making it more difficult for germs and disease to spread.
  • the hydroxyl radical is present in high concentrations in tropospheric air due to the presence of related trosposheric components, principally ozone and unsaturated hydrocarbons. These components are missing or much reduced in indoor air thus causing the concentration of hydroxyl radicals to be correspondingly low.
  • the Applicant's earlier invention re-creates tropospheric conditions indoors to increase the population of hydroxyl radicals which acts to reduce the level of harmful contaminants, particularly pathogenic bacterial and viruses, within an indoor or enclosed environment.
  • an apparatus for the decontamination of air comprising a housing having an air inlet and an air outlet with an air passage therebetween, means for directing a stream of air through the housing, the housing containing a non-thermal plasma cell, an ultraviolet emitting device and an ozone depletion catalyst, the non-thermal plasma comprising an anode, a dielectric and a cathode, the cathode being in the form of a meshed enclosure which surrounds the ultraviolet emitting device and ozone depletion catalyst to form a reaction chamber and Faraday cage.
  • a hydrocarbon emitter is provided within the housing downstream of the rection chamber, preferably adjacent or in the vicinity of the outlet.
  • a water droplet emitter preferably in the form of an atomiser, may be provided to deliver an ultra-fine spray of de-ionised water into the reaction chamber. It is to be appreciated that the hydrocarbon emitter and water droplet emitter would be connected to suitable source reservoirs having appropriate delivery mechanisms.
  • the housing may also include means for delivering microwaves of a certain wavelength to the reaction chamber, such as a magnetron. This removes the need of a separate power circuit to the ultraviolet emitting device.
  • a fan or impellor is preferably provided at or in the vicinity of the inlet for directing air through the passage.
  • the anode preferably comprises a reticulated conductive or semi-conductive element, such as a carbon and aluminium composite.
  • the dielectric may be any suitable non-conducting material or insulator.
  • the dielectric comprises activated alumina pellets.
  • the material may be coated with a catalytic material.
  • the dielectric comprises deionised water droplets or vapour.
  • an apparatus for the decontamination of air comprising a housing having an air inlet and an air outlet with an air passage therebetween, means for directing a stream of air through the housing, the housing containing a non-thermal plasma cell, an ultraviolet emitting device and an ozone depletion catalyst, the non-thermal plasma comprising an anode, a dielectric and a cathode, the dielectric comprising deionised water droplets or vapour.
  • the cathode preferably comprises a porous mesh of conducting material that is formed into a cage-like structure for surrounding the UV emitting device and catalyst.
  • the cathode also houses a microwave emitter for delivering microwaves of a certain wavelength to excite the UV emitting device.
  • the microwave emitter generates wavelengths in the Radio Frequency range 2200-2600 MHz, such as 2450 MHz.
  • the catalyst it is preferably for the catalyst to surround the UV emitting device.
  • the UV emitting device is tubular and surrounded by a mesh of an ozone-catalysing device.
  • the coating on the mesh forms the catalyst.
  • Appropriate supporting members may be provided between the cage and the UV emitter/catalyst and/or between the emitter and the catalyst.
  • the supporting elements are preferably coated with a material that acts as a catalyst to the reaction and may be profiled to impart a swirling motion to the air passing through the reaction chamber.
  • the plasma cell for the apparatus may be provided in alternate forms to increase the efficiency of the device.
  • a third aspect of the present invention provides a non-thermal plasma cell for an apparatus for the decontamination of air, the plasma cell comprising an anode and a cathode with a dielectric therebetween, the dielectric comprising deionised water droplets or vapour.
  • the cell should have a suitable power supply to the anode.
  • the cathode is earthed.
  • the cathode of the non-thermal plasma cell according to the third aspect of the invention comprises a hollow tube of conducting material.
  • the anode is preferably provided within the tube spaced apart from the walls forming the cathode to provide a dielectric space therebetween. More preferably, the anode is fixed centrally within the tube.
  • a water reservoir is connected to the dielectric space.
  • An air inlet is also provided for delivering air to the reservoir.
  • An atomiser may be provided for providing a fine mist of water droplets within the space.
  • Appropriate air movement means such as a fan, is preferably provided to propel the water droplets into the dielectric space.
  • the plasma cell may also be provided with a further air inlet for delivering air from an alternative source, such as air from the surrounding environment, to the dielectric space. Again air movement means may be provided to assist this delivery.
  • a plasma cell according to the third aspect of the present invention may be provided within an air decontamination device comprising a housing having an air inlet and an air outlet with an air passage therebetween, means for directing a stream of air through the housing, the housing containing the non-thermal plasma cell, an ultraviolet emitting device and an ozone depletion catalyst.
  • a non thermal plasma cell comprising a columnar cell having a substantially central anode surrounded by a cathode with dielectric therebetween.
  • the cathode forms the wall of the column.
  • the column may be any three-dimensional shape but preferably is cylindrical.
  • the column may be a polygon having at least five sides.
  • the polygon is a regular polygon.
  • the cathode is comprised of a mesh of conducting material that surrounds the dielectric provided between the anode and cathode.
  • Any appropriate non-conducting material may be used for the dielectric, but preferable materials are activated alumina pellets or deionised water droplets.
  • a suitable power supply should be provided to the anode and the cathode is preferably earthed.
  • the individual columnar cells may be arranged into an array to form an enlarged non-thermal plasma body.
  • the array may be incorporated into an air decontamination device to provide a plasma field for the passage of air to be decontaminated that has reduced back pressure against the flow of air.
  • a fifth aspect of the present invention provides an array of non-thermal plasma cells, the array comprising a plurality of non-thermal plasma cells.
  • the array of non-thermal plasma cells may be provided within an air decontamination device comprising a housing having an air inlet and an air outlet with an air passage therebetween, means for directing a stream of air through the housing, the housing containing the array of non-thermal plasma cells, an ultraviolet emitting device and an ozone depletion catalyst.
  • the array preferably comprises multiple rows of the columnar cells according to a fourth aspect of the present invention, adjacent rows being staggered with respect to one another.
  • the individual cells making up the array may be sequentially switched at a frequency sufficient to maintain a non-thermal plasma in the individual cells, even though the power supplying that cell is momentarily absent. Such sequential switching may be obtained by any suitable means known in the art, such as using proprietary automotive distribution technology, electro-mechanical or solid-state.
  • an outer wall housing the array of plasma cells prefferably be insulated, for example with a laminated structure, such as silicone rubber.
  • baffles may be provided at locations within or surrounding the array to aid air flow therethrough.
  • FIG. 1 shows a longitudinal cross-sectional view of an air decontamination device, in accordance with a first aspect of the invention
  • FIG. 2 is a transverse cross-sectional view through the device shown in FIG. 1 ;
  • FIG. 3 a is schematic diagram of a non-thermal plasma cell according to another aspect of the present invention.
  • FIG. 3 b is a transverse cross-section through A-A shown in FIG. 3 a;
  • FIG. 4 is a longitudinal cross-sectional top view of an array of non-thermal plasma cells according to yet another aspect of the present invention.
  • FIG. 5 is a vertical cross-section through a single plasma cell for the array shown in FIG. 4 ;
  • FIG. 6 is a schematic partial end view of the array of non-thermal plasma cells shown in FIG. 4 .
  • an air decontamination device according to a first aspect of the present invention which comprises a housing 1 having a flow passage 2 , an air inlet 4 to the flow passage 2 and an air outlet 6 exiting from the passage 2 .
  • An air stream generator in the form of a fan or impeller 20 is provided for forcing air through the housing 1 .
  • a grill (not shown) may be provided across the air inlet 4 to prevent accidental access to the impellor while in operation.
  • a power supply (not shown) may be a proprietary product but should be capable of supplying a power of 12-25 Kv at between 10-30 KHz.
  • a non-thermal plasma filter identified collectively as 30 in FIG. 1 , comprises an anode or high voltage electrode 31 , a dielectric 32 and a porous mesh 33 in the form of a cage which functions not only as the cathode but also the end of the reaction chamber.
  • the anode 31 comprises reticulated (three dimensionally porous) conductive elements, in this case being aluminium and carbon composite. However, any rigid reticulated conductive or semi-conductive material could be used.
  • the dielectric 32 is activated alumina pellets, nominally 3 to 4 millimeters in diameter. However, again, the dielectric 32 could be any suitable material to suit varying applications and specific requirements.
  • the dielectric may consist of a non-conductive matrix of porous foam and/or may be coated with a catalytic material.
  • the catalyst may be selected to target the destruction of a specific compound or group of compounds.
  • the cathode 33 comprises a porous mesh of conducting material, such as an expanded stainless steel mesh, which substantially follows the internal contours of the housing to form a hollow cage.
  • the cage may have an internal coating of UV catalysing material, in this case Anatase form Titanium dioxide.
  • the cage formed by the cathode 33 houses an ultraviolet radiation emitting device 40 comprising an ultraviolet tube surrounded by a photocatalytic element 42 .
  • the cage also incorporates a microwave emitter 60 connected to a magnetron 62 .
  • a discharge nozzle or orifice 70 is provided in the cage which is connected to a deionised water reservoir 72 for delivering a fine spray of deionised water 75 .
  • a hydrocarbon emitter shown collectively as 50 in FIG. 1 , is provided downstream of the Faraday cage adjacent to or in the vicinity of the exit 6 from the housing 1 .
  • the hydrocarbon emitter 50 includes a rechargeable hydrocarbon reservoir 55 containing a liquid aromatic hydrocarbon, for example an olefin such as a Terpene.
  • the delivery system of the hydrocarbon emitter 50 comprises a threaded bar 52 which passes through to a stepper motor 53 . The bar pushes a piston 54 through the reservoir 55 to force the hydrocarbon through a tube 56 and out of a spray head 57 .
  • any other suitable means for supplying volatised aromatic hydrocarbon to the airstream may be used.
  • the air decontamination device can be solely powered by mains electricity, solely powered by battery packs, which may be rechargeable, or may be selectively energisable by both power sources.
  • the air decontamination device can be produced in the form of a portable device, and this can take the dimensions of or substantially of a small briefcase. Alternatively, the air decontamination device can be produced as a larger device intended to remain in one location once installed. The latter device is more suitable for, but not limited to, industrial or commercial installations and premises.
  • the air decontamination device In use, the air decontamination device is positioned in the location to be decontaminated.
  • the device is intended to decontaminate air within a building, chamber, enclosure, trunking, pipe, channel or other enclosed or substantially enclosed area. However, with sufficient through-flow capacity, it can also decontaminate air in an open outside environment.
  • the device is energised, and the fan 20 generates a stream of ambient air along the passage 2 of the housing 1 , as indicated by the arrows in FIG. 1 .
  • the air stream initially encounters the anode 31 , dielectric 32 and cathode 33 which form the non-thermal plasma filter 30 .
  • the filter utilises the characteristics of a non-thermal plasma to ‘plasmalyse’ the constituent parts of the air within the dielectric core.
  • the outer ring electrons in the atomic structure of the elements comprising air principally oxygen and nitrogen
  • the energised electrons release energy through collisions.
  • the free radicals are powerful oxidants, and will oxidise hydrocarbons, organic gases, and particles typically PM 2.5 (2.5 ⁇ 10 ⁇ 6 meters) and below, such as bacteria, viruses, spores, yeast moulds and odours. Only the most inert elements or compounds will generally resist oxidation.
  • the non-thermal plasma filter 30 produces ozone as one of the by-products.
  • the half-life of ozone is dependent on atmospheric conditions and, itself being a powerful oxidant, under normal circumstances will continue to react in the air long after it has exited the plasma core. This is unacceptable for a device operated by and in the general vicinity of people. Therefore, the Faraday cage formed by the cathode of the plasma filter houses a UV light emitting tube 40 surrounded by a mesh of an ozone-catalysing device 42 .
  • the mercury within the UV light emitting tube is excited by microwaves generated in the Megahertz frequency by the magnetron 62 of fixed or variable output.
  • the ultraviolet radiation is emitted with peaks typically at 254 and 313 nanometers wavelength which act to break down the ozone entrained in the air stream.
  • the coating on the mesh 42 acts to catalyse this break down.
  • the use of microwaves to excite the UV light removes the need for separate circuitry to power the UV tube thereby reducing component complexity and numbers.
  • the microwaves also serve to excite the water molecules which exist in the emissions from the plasma cell due to the oxidation of hydrocarbons which will also benefit the efficiency of the plasma cell.
  • microwaves in this frequency increase the intensity of non-thermal plasma fields, thereby serving to increase the overall efficiency of the device.
  • the (optional) introduction of a deionised water mist 75 from the reservoir 72 is sufficient to increase the relative humidity of the air passing through the device to >90%. This serves to increase the yield of hydroxyl radicals (OH.) and reduce the level of free ozone and oxides of nitrogen (NOx) in the emissions from the plasma cell.
  • the deionised water should have a resistance of or about 18.2 M ⁇ /cm. Increasing the population of OH. free radicals at this stage of the process increases the efficiency of the subsequent stages early in the reaction's kinetic pathway, thus reducing the need for ozone in the air emitted by the process.
  • the dual function Faraday cage/reaction chamber also incorporates supports 90 for the UV emitting tube 40 . These supports are coated with a material that catalyses the breakdown of ozone with water molecules into OH. free radicals and further are shaped to induce a swirl or rotation to the air passing through the chamber.
  • a suitable coating material is Anatase form of titanium dioxide. It is preferable for all internal surfaces 11 to be similarly coated.
  • This destruction (photo-oxidation) of the ozone increases the free radical level, and particularly the level of Hydroxyl radicals OH ⁇ , within the air stream. These free radicals also vigorously oxidise contaminants remaining within the air stream.
  • the treated air that has passed through the reaction chamber and is emitted from the mesh 33 is rich in OH. radicals and contains a small amount of ozone, typically ⁇ 100 ppb, and water vapour.
  • the exhaust air is mixed with a measured volume of a hydrocarbon introduced by the spray head 57 .
  • the hydrocarbon is preferably a terpene, typically myrcene, which has no known toxicity.
  • the unsaturated double bonds in the terpene molecule react preferentially with ozone, yielding more OH. radicals. This ozone-terpene reaction takes place within the device of the present invention, so that only the reactant products which in turn generate OH.
  • the rate of rotation of the stepper motor 53 of the hydrocarbon emitter 50 governs the rate of delivery of the terpene.
  • the rate of terpene delivery can be precisely controlled thereby ensuring that the mass of free ozone in the exhaust is reacted with the appropriate mass of terpene.
  • the air stream resulting from these reactions contains a cascade reaction known as “Open Air factor” which mimics a natural process in outdoor air which is responsible for the continuous decontamination of outdoor air.
  • the products of these preferential reactions have zero vapour pressure, and hence condense on any remaining particle in the air stream or surface. As a result, once the decontaminated air stream exits through the outlet 6 of the housing 1 , decontamination of contaminants within the ambient air, and less quickly, on surfaces occurs.
  • the small particulates are actually beneficial in that they fuel the production of hydroxyl radicals within the plasma filter 30 once recirculated.
  • the potential for a visible fog is undesirable, it is beneficial in increasing the efficiency of the decontamination device, and thus the resultant safety of the ambient air.
  • the power supply for the device preferably incorporates a feedback circuit which enables the non-thermal plasma cell to operate at the optimum resonant frequency for that plasma cell under varying environmental conditions. It has been observed in experimentation that the resonant frequency of the cell and its capacitance vary considerably when the components of the air passing through the cell themselves vary from the norm. Thus enabling the power supply to constantly match the varying resonance will ensure optimum efficiency.
  • the power supply preferably incorporates a detector circuit (not shown) which monitors changes in capacitance and resonant frequency.
  • the signal from this circuit may require amplification.
  • the signal may be used to drive an indicator which will signal to an operator that the air component conditions have changed, for example, to provide warning of a gas or biological attack.
  • This signal may also be used to operate a switch to engage multiple or duplicated components located within the device thereby providing an increased decontamination effort in response to an increased challenge.
  • the air stream generator can be driven in reverse, enabling decontamination of the interior of the device by drawing excess free radicals entrained in the air stream back through the device. As such, the device is largely self-cleaning.
  • FIGS. 3 a and 3 b of the accompanying drawings illustrate an alternative aspect of the present invention wherein the dielectric of the plasma cell is replaced with a fine mist of de-ionised water.
  • This embodiment minimises back pressure on the air delivery system reducing energy requirements and noise.
  • water droplets in the non-thermal plasma dramatically increase the yield of OH. radicals, as well as reducing ozone levels by increasing hydrogen peroxide levels and peroxone (or peroxozone) over the more traditional “dielectric sandwich” plasma design previously employed.
  • the plasma cell 200 comprises a tubular component 201 wherein the wall of the tube serves as the cathode, the tube having a centrally fixed anode 203 connected to a high voltage/high frequency power supply 205 necessary to create a non-thermal plasma in the dielectric space 210 provided between the anode and the cathode.
  • the cathode is earthed 212 .
  • the dielectric in the dielectric space 210 is provided by a fine mist of deionised water.
  • the water droplets should be small enough to float freely in the air and this may be achieved by using, for example, a proprietary ultrasonic atomiser provided in a reservoir 220 .
  • a fan 222 drives the de-ionised water vapour from the reservoir into the dielectric space 210 and an air inlet 230 supplies feed air into the reservoir where it is saturated with the water mist and propelled B into the tubular plasma cell 200 .
  • Air C from the surrounding environment i.e. a room or chamber to be decontaminated
  • Fan 245 Air C from the surrounding environment (i.e. a room or chamber to be decontaminated) is introduced via a separate inlet 240 and propelled into the dielectric space by fan 245 .
  • the control of the relative speeds of the fans 222 , 245 enables the control and adjustment of the population of de-ionised water droplets in the dielectric space.
  • FIGS. 4 to 6 of the accompanying drawings illustrate an alternative plasma cell 300 , and an array of such cells 400 , according another aspect of the present invention.
  • Each plasma cell 300 of an array 400 is columnar and has a central high-voltage, high-frequency electrode 302 surrounded by a dielectric of activated alumina pellets 304 , typically 5-6 mm in diameter.
  • the activated alumina pellets are held in position relative to the central anode by means of a cathode mesh 306 , of a size suitable to retain the pellets.
  • a suitable power supply 315 typically 10 Kv at 20 KHz
  • a non-thermal plasma is created in the dielectric 304 between the anode 302 and cathode 306 . It has been demonstrated by experimentation that the effective non-thermal plasma field 308 (illustrated by broken lines in FIGS. 4 and 5 ) extends some way beyond the physical size of the cell, probably due to electrons freed by the energy created within the cell.
  • each outer wall of the array is provided with insulation, for example in the form of a laminated structure 310 , for example of silicone rubber, as shown in FIG. 5 .
  • baffles 312 are provided on the internal the wall of the array 400 and between rows of the cells to guide air between the individual plasma cells 300 .
  • the plasma fields 308 touch or overlap (depending upon the spacing of the cells and field applied) and thus the air cannot pass through the array without entering a plasma state.
  • the physical control of the air directs the air stream at the plasma columns, ensuring larger particles and molecules are adsorbed partially on to the dielectric material 304 , allowing a longer exposure to the plasma field 308 , and the inherent oxidative action, that acts to destroy these larger contaminants.
  • the individual cells making up the array may be sequentially switched at a frequency sufficient to maintain a non-thermal plasma in the individual cells, even though the power supplying that cell is momentarily absent. This relies on the observation that a pulsed non-thermal plasma state exists for several hundredths of second longer than the pulse of electrical energy required to create it. Such sequential switching may be obtained by using proprietary automotive distribution technology, electro-mechanical or solid-state.

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Abstract

An apparatus for the decontamination of air, the apparatus comprising a housing (1) having an air inlet (4) and an air outlet (6) with an air passage (2) there between, means (20) for directing a stream of air through the housing, the housing containing a non-thermal plasma cell (30), an ultraviolet emitting device (40) and an ozone depletion catalyst (42), the non-thermal plasma comprising an anode (32), a dielectric (32) and a cathode (33), the cathode being in the form of a meshed enclosure which surrounds the ultraviolet emitting device and ozone depletion catalyst to form a reaction chamber and Faraday cage. The non-thermal plasma cell may also be provided as a columnar cell for forming an array of cells and the dielectric may comprise water droplets to improve the efficiency of the device.

Description

The present invention relates to an improved device for the decontamination of air and surfaces.
Air purity and being able to consistently remove contaminants entrained in the air is extremely important, especially in supposedly sterile or hygienic environments, such as hospitals and kitchens. It is also beneficial having decontaminated air in doctors' surgeries, and workplace environments making it more difficult for germs and disease to spread.
In addition to microbiological contaminants, chemical gases or vapours can present a serious hazard, either as a by-product of industrial processing or as a malicious attack through terrorism or chemical warfare.
The Applicant's earlier patent (EP1799330) provides an efficient method and active component is the hydroxyl radical (OH) which is second only to fluorine as an oxidising species but has the advantage of having no significant toxicity to higher organisms, while being lethal to pathogenic bacteria and viruses.
The hydroxyl radical is present in high concentrations in tropospheric air due to the presence of related trosposheric components, principally ozone and unsaturated hydrocarbons. These components are missing or much reduced in indoor air thus causing the concentration of hydroxyl radicals to be correspondingly low. The Applicant's earlier invention re-creates tropospheric conditions indoors to increase the population of hydroxyl radicals which acts to reduce the level of harmful contaminants, particularly pathogenic bacterial and viruses, within an indoor or enclosed environment.
Whilst the process and device of the Applicant's earlier disclosure has been found to be highly effective at re-creating an outdoor environment indoors, there is always room for enhancing its efficiency and reliability.
It is an aim of the present invention to provide an improved apparatus for the decontamination of air and surfaces.
According to a first aspect of the present invention, there is provided an apparatus for the decontamination of air, the apparatus comprising a housing having an air inlet and an air outlet with an air passage therebetween, means for directing a stream of air through the housing, the housing containing a non-thermal plasma cell, an ultraviolet emitting device and an ozone depletion catalyst, the non-thermal plasma comprising an anode, a dielectric and a cathode, the cathode being in the form of a meshed enclosure which surrounds the ultraviolet emitting device and ozone depletion catalyst to form a reaction chamber and Faraday cage.
Preferably, a hydrocarbon emitter is provided within the housing downstream of the rection chamber, preferably adjacent or in the vicinity of the outlet. Alternatively or additionally, a water droplet emitter, preferably in the form of an atomiser, may be provided to deliver an ultra-fine spray of de-ionised water into the reaction chamber. It is to be appreciated that the hydrocarbon emitter and water droplet emitter would be connected to suitable source reservoirs having appropriate delivery mechanisms.
The housing may also include means for delivering microwaves of a certain wavelength to the reaction chamber, such as a magnetron. This removes the need of a separate power circuit to the ultraviolet emitting device.
A fan or impellor is preferably provided at or in the vicinity of the inlet for directing air through the passage.
The anode preferably comprises a reticulated conductive or semi-conductive element, such as a carbon and aluminium composite. The dielectric may be any suitable non-conducting material or insulator. In one preferred embodiment, the dielectric comprises activated alumina pellets. The material may be coated with a catalytic material. In an alternative embodiment of the invention, the dielectric comprises deionised water droplets or vapour.
To this end there is provided an apparatus for the decontamination of air, the apparatus comprising a housing having an air inlet and an air outlet with an air passage therebetween, means for directing a stream of air through the housing, the housing containing a non-thermal plasma cell, an ultraviolet emitting device and an ozone depletion catalyst, the non-thermal plasma comprising an anode, a dielectric and a cathode, the dielectric comprising deionised water droplets or vapour.
The cathode preferably comprises a porous mesh of conducting material that is formed into a cage-like structure for surrounding the UV emitting device and catalyst. Preferably, the cathode also houses a microwave emitter for delivering microwaves of a certain wavelength to excite the UV emitting device. Preferably, the microwave emitter generates wavelengths in the Radio Frequency range 2200-2600 MHz, such as 2450 MHz.
It is preferably for the catalyst to surround the UV emitting device. Preferably, the UV emitting device is tubular and surrounded by a mesh of an ozone-catalysing device. Preferably, the coating on the mesh forms the catalyst.
Appropriate supporting members may be provided between the cage and the UV emitter/catalyst and/or between the emitter and the catalyst. The supporting elements are preferably coated with a material that acts as a catalyst to the reaction and may be profiled to impart a swirling motion to the air passing through the reaction chamber.
The plasma cell for the apparatus may be provided in alternate forms to increase the efficiency of the device. The replacement of the dielectric with fine deionised water droplets, preferably with a minimum resistance of typically 18 MΩ/cm, minimises back pressure on the air delivery system reducing energy requirements and noise and further, increases the yield of OH. radicals.
To this end, a third aspect of the present invention provides a non-thermal plasma cell for an apparatus for the decontamination of air, the plasma cell comprising an anode and a cathode with a dielectric therebetween, the dielectric comprising deionised water droplets or vapour.
It is to be appreciated that the cell should have a suitable power supply to the anode. Preferably, the cathode is earthed.
Preferably, the cathode of the non-thermal plasma cell according to the third aspect of the invention comprises a hollow tube of conducting material. The anode is preferably provided within the tube spaced apart from the walls forming the cathode to provide a dielectric space therebetween. More preferably, the anode is fixed centrally within the tube.
Preferably, a water reservoir is connected to the dielectric space. An air inlet is also provided for delivering air to the reservoir. An atomiser may be provided for providing a fine mist of water droplets within the space. Appropriate air movement means, such as a fan, is preferably provided to propel the water droplets into the dielectric space.
The plasma cell may also be provided with a further air inlet for delivering air from an alternative source, such as air from the surrounding environment, to the dielectric space. Again air movement means may be provided to assist this delivery.
It is to be appreciated that a plasma cell according to the third aspect of the present invention may be provided within an air decontamination device comprising a housing having an air inlet and an air outlet with an air passage therebetween, means for directing a stream of air through the housing, the housing containing the non-thermal plasma cell, an ultraviolet emitting device and an ozone depletion catalyst.
According to a fourth aspect of the present invention there is provided a non thermal plasma cell comprising a columnar cell having a substantially central anode surrounded by a cathode with dielectric therebetween.
Preferably, the cathode forms the wall of the column. The column may be any three-dimensional shape but preferably is cylindrical. Alternatively, the column may be a polygon having at least five sides. Preferably, the polygon is a regular polygon.
It is preferable for the cathode to be comprised of a mesh of conducting material that surrounds the dielectric provided between the anode and cathode. Any appropriate non-conducting material may be used for the dielectric, but preferable materials are activated alumina pellets or deionised water droplets.
A suitable power supply should be provided to the anode and the cathode is preferably earthed.
The individual columnar cells may be arranged into an array to form an enlarged non-thermal plasma body. The array may be incorporated into an air decontamination device to provide a plasma field for the passage of air to be decontaminated that has reduced back pressure against the flow of air.
To this end, a fifth aspect of the present invention provides an array of non-thermal plasma cells, the array comprising a plurality of non-thermal plasma cells. The array of non-thermal plasma cells may be provided within an air decontamination device comprising a housing having an air inlet and an air outlet with an air passage therebetween, means for directing a stream of air through the housing, the housing containing the array of non-thermal plasma cells, an ultraviolet emitting device and an ozone depletion catalyst.
The array preferably comprises multiple rows of the columnar cells according to a fourth aspect of the present invention, adjacent rows being staggered with respect to one another. The individual cells making up the array may be sequentially switched at a frequency sufficient to maintain a non-thermal plasma in the individual cells, even though the power supplying that cell is momentarily absent. Such sequential switching may be obtained by any suitable means known in the art, such as using proprietary automotive distribution technology, electro-mechanical or solid-state.
It is preferable for an outer wall housing the array of plasma cells to be insulated, for example with a laminated structure, such as silicone rubber.
Optionally, baffles may be provided at locations within or surrounding the array to aid air flow therethrough.
The present invention will now be more particularly described, by way of example, with reference to the accompanying drawings, in which:
FIG. 1 shows a longitudinal cross-sectional view of an air decontamination device, in accordance with a first aspect of the invention;
FIG. 2 is a transverse cross-sectional view through the device shown in FIG. 1;
FIG. 3 a is schematic diagram of a non-thermal plasma cell according to another aspect of the present invention;
FIG. 3 b is a transverse cross-section through A-A shown in FIG. 3 a;
FIG. 4 is a longitudinal cross-sectional top view of an array of non-thermal plasma cells according to yet another aspect of the present invention;
FIG. 5 is a vertical cross-section through a single plasma cell for the array shown in FIG. 4; and
FIG. 6 is a schematic partial end view of the array of non-thermal plasma cells shown in FIG. 4.
Referring to FIGS. 1 and 2 of the accompanying drawings, there is shown an air decontamination device according to a first aspect of the present invention which comprises a housing 1 having a flow passage 2, an air inlet 4 to the flow passage 2 and an air outlet 6 exiting from the passage 2. An air stream generator in the form of a fan or impeller 20 is provided for forcing air through the housing 1. As a safety measure, a grill (not shown) may be provided across the air inlet 4 to prevent accidental access to the impellor while in operation. A power supply (not shown) may be a proprietary product but should be capable of supplying a power of 12-25 Kv at between 10-30 KHz.
A non-thermal plasma filter, identified collectively as 30 in FIG. 1, comprises an anode or high voltage electrode 31, a dielectric 32 and a porous mesh 33 in the form of a cage which functions not only as the cathode but also the end of the reaction chamber.
The anode 31 comprises reticulated (three dimensionally porous) conductive elements, in this case being aluminium and carbon composite. However, any rigid reticulated conductive or semi-conductive material could be used. The dielectric 32 is activated alumina pellets, nominally 3 to 4 millimeters in diameter. However, again, the dielectric 32 could be any suitable material to suit varying applications and specific requirements. The dielectric may consist of a non-conductive matrix of porous foam and/or may be coated with a catalytic material. The catalyst may be selected to target the destruction of a specific compound or group of compounds. The cathode 33 comprises a porous mesh of conducting material, such as an expanded stainless steel mesh, which substantially follows the internal contours of the housing to form a hollow cage. This is able to act as a “Faraday Cage” serving, to block out external static electrical fields and allow only radiation of a certain wavelength to enter the interior of the cage. The cage may have an internal coating of UV catalysing material, in this case Anatase form Titanium dioxide.
The cage formed by the cathode 33 houses an ultraviolet radiation emitting device 40 comprising an ultraviolet tube surrounded by a photocatalytic element 42. The cage also incorporates a microwave emitter 60 connected to a magnetron 62. Additionally, a discharge nozzle or orifice 70 is provided in the cage which is connected to a deionised water reservoir 72 for delivering a fine spray of deionised water 75.
A hydrocarbon emitter, shown collectively as 50 in FIG. 1, is provided downstream of the Faraday cage adjacent to or in the vicinity of the exit 6 from the housing 1. The hydrocarbon emitter 50 includes a rechargeable hydrocarbon reservoir 55 containing a liquid aromatic hydrocarbon, for example an olefin such as a Terpene. The delivery system of the hydrocarbon emitter 50 comprises a threaded bar 52 which passes through to a stepper motor 53. The bar pushes a piston 54 through the reservoir 55 to force the hydrocarbon through a tube 56 and out of a spray head 57. However, it is to be appreciated that any other suitable means for supplying volatised aromatic hydrocarbon to the airstream may be used.
The air decontamination device can be solely powered by mains electricity, solely powered by battery packs, which may be rechargeable, or may be selectively energisable by both power sources.
The air decontamination device can be produced in the form of a portable device, and this can take the dimensions of or substantially of a small briefcase. Alternatively, the air decontamination device can be produced as a larger device intended to remain in one location once installed. The latter device is more suitable for, but not limited to, industrial or commercial installations and premises.
In use, the air decontamination device is positioned in the location to be decontaminated. The device is intended to decontaminate air within a building, chamber, enclosure, trunking, pipe, channel or other enclosed or substantially enclosed area. However, with sufficient through-flow capacity, it can also decontaminate air in an open outside environment.
The device is energised, and the fan 20 generates a stream of ambient air along the passage 2 of the housing 1, as indicated by the arrows in FIG. 1. The air stream initially encounters the anode 31, dielectric 32 and cathode 33 which form the non-thermal plasma filter 30. The filter utilises the characteristics of a non-thermal plasma to ‘plasmalyse’ the constituent parts of the air within the dielectric core. In general terms, the outer ring electrons in the atomic structure of the elements comprising air (principally oxygen and nitrogen) are ‘excited’ by the intense electronic field generated by the non-thermal plasma, typically being 10 Kv at 20 KHz. The energised electrons release energy through collisions. However, little or no heat is emitted due to the insubstantial mass of the electrons and the consequent lack of ionisation that occurs. The released energy is sufficient to generated free radicals within the air stream, such as O. and OH. The free radicals are powerful oxidants, and will oxidise hydrocarbons, organic gases, and particles typically PM 2.5 (2.5×10−6 meters) and below, such as bacteria, viruses, spores, yeast moulds and odours. Only the most inert elements or compounds will generally resist oxidation.
Since many of the resultants of the oxidative reactions are transient and surface acting, due to having zero vapour pressure, by providing a molecular thick catalytic coating on some or all of the dielectric material of the non-thermal plasma, oxidation of particular molecules or compounds, for example nerve gas agents, within the non-thermal plasma can be targeted.
The non-thermal plasma filter 30 produces ozone as one of the by-products. The half-life of ozone is dependent on atmospheric conditions and, itself being a powerful oxidant, under normal circumstances will continue to react in the air long after it has exited the plasma core. This is unacceptable for a device operated by and in the general vicinity of people. Therefore, the Faraday cage formed by the cathode of the plasma filter houses a UV light emitting tube 40 surrounded by a mesh of an ozone-catalysing device 42. The mercury within the UV light emitting tube is excited by microwaves generated in the Megahertz frequency by the magnetron 62 of fixed or variable output. The ultraviolet radiation is emitted with peaks typically at 254 and 313 nanometers wavelength which act to break down the ozone entrained in the air stream. The coating on the mesh 42 acts to catalyse this break down. The use of microwaves to excite the UV light removes the need for separate circuitry to power the UV tube thereby reducing component complexity and numbers.
The microwaves also serve to excite the water molecules which exist in the emissions from the plasma cell due to the oxidation of hydrocarbons which will also benefit the efficiency of the plasma cell. This requires the mesh of the cathode component 33 to be wide enough to allow microwave energy to pass through the cage, to enter the plasma cell. Furthermore, it is widely known that microwaves in this frequency increase the intensity of non-thermal plasma fields, thereby serving to increase the overall efficiency of the device.
The (optional) introduction of a deionised water mist 75 from the reservoir 72 is sufficient to increase the relative humidity of the air passing through the device to >90%. This serves to increase the yield of hydroxyl radicals (OH.) and reduce the level of free ozone and oxides of nitrogen (NOx) in the emissions from the plasma cell. The deionised water should have a resistance of or about 18.2 MΩ/cm. Increasing the population of OH. free radicals at this stage of the process increases the efficiency of the subsequent stages early in the reaction's kinetic pathway, thus reducing the need for ozone in the air emitted by the process.
The dual function Faraday cage/reaction chamber also incorporates supports 90 for the UV emitting tube 40. These supports are coated with a material that catalyses the breakdown of ozone with water molecules into OH. free radicals and further are shaped to induce a swirl or rotation to the air passing through the chamber. A suitable coating material is Anatase form of titanium dioxide. It is preferable for all internal surfaces 11 to be similarly coated.
This destruction (photo-oxidation) of the ozone increases the free radical level, and particularly the level of Hydroxyl radicals OH, within the air stream. These free radicals also vigorously oxidise contaminants remaining within the air stream.
Trials have shown that free radicals resident in the air stream post-plasma filtering significantly increase the rate of generation of hydroxyl radicals during the photo-oxidative process.
The treated air that has passed through the reaction chamber and is emitted from the mesh 33 is rich in OH. radicals and contains a small amount of ozone, typically <100 ppb, and water vapour. In order to ensure that no significant ozone enters the chamber to be treated, the exhaust air is mixed with a measured volume of a hydrocarbon introduced by the spray head 57. The hydrocarbon is preferably a terpene, typically myrcene, which has no known toxicity. The unsaturated double bonds in the terpene molecule react preferentially with ozone, yielding more OH. radicals. This ozone-terpene reaction takes place within the device of the present invention, so that only the reactant products which in turn generate OH. radicals are emitted into the chamber/enclosure to be treated. The rate of rotation of the stepper motor 53 of the hydrocarbon emitter 50 governs the rate of delivery of the terpene. By linking the stepper motor to a control panel (not shown) the rate of terpene delivery can be precisely controlled thereby ensuring that the mass of free ozone in the exhaust is reacted with the appropriate mass of terpene. The air stream resulting from these reactions contains a cascade reaction known as “Open Air factor” which mimics a natural process in outdoor air which is responsible for the continuous decontamination of outdoor air.
The products of these preferential reactions have zero vapour pressure, and hence condense on any remaining particle in the air stream or surface. As a result, once the decontaminated air stream exits through the outlet 6 of the housing 1, decontamination of contaminants within the ambient air, and less quickly, on surfaces occurs.
These initiated condensation reactions outside of the decontamination device may cause small particulate ‘growing’, resulting, in extreme cases, in a visible fog or mist. This is undesirable. However, due to the air decontamination device effectively recirculating and re-decontaminating air within an environment, these small particulates are in any event removed within the non-thermal plasma filter 22.
The small particulates are actually beneficial in that they fuel the production of hydroxyl radicals within the plasma filter 30 once recirculated. Thus, although the potential for a visible fog is undesirable, it is beneficial in increasing the efficiency of the decontamination device, and thus the resultant safety of the ambient air.
The power supply for the device preferably incorporates a feedback circuit which enables the non-thermal plasma cell to operate at the optimum resonant frequency for that plasma cell under varying environmental conditions. It has been observed in experimentation that the resonant frequency of the cell and its capacitance vary considerably when the components of the air passing through the cell themselves vary from the norm. Thus enabling the power supply to constantly match the varying resonance will ensure optimum efficiency.
Furthermore, the power supply preferably incorporates a detector circuit (not shown) which monitors changes in capacitance and resonant frequency. The signal from this circuit may require amplification. The signal may be used to drive an indicator which will signal to an operator that the air component conditions have changed, for example, to provide warning of a gas or biological attack. This signal may also be used to operate a switch to engage multiple or duplicated components located within the device thereby providing an increased decontamination effort in response to an increased challenge.
The air stream generator can be driven in reverse, enabling decontamination of the interior of the device by drawing excess free radicals entrained in the air stream back through the device. As such, the device is largely self-cleaning.
FIGS. 3 a and 3 b of the accompanying drawings illustrate an alternative aspect of the present invention wherein the dielectric of the plasma cell is replaced with a fine mist of de-ionised water. This embodiment minimises back pressure on the air delivery system reducing energy requirements and noise. Furthermore the presence of water droplets in the non-thermal plasma dramatically increase the yield of OH. radicals, as well as reducing ozone levels by increasing hydrogen peroxide levels and peroxone (or peroxozone) over the more traditional “dielectric sandwich” plasma design previously employed.
In further detail, the plasma cell 200 comprises a tubular component 201 wherein the wall of the tube serves as the cathode, the tube having a centrally fixed anode 203 connected to a high voltage/high frequency power supply 205 necessary to create a non-thermal plasma in the dielectric space 210 provided between the anode and the cathode. The cathode is earthed 212.
The dielectric in the dielectric space 210 is provided by a fine mist of deionised water. The water droplets should be small enough to float freely in the air and this may be achieved by using, for example, a proprietary ultrasonic atomiser provided in a reservoir 220. A fan 222 drives the de-ionised water vapour from the reservoir into the dielectric space 210 and an air inlet 230 supplies feed air into the reservoir where it is saturated with the water mist and propelled B into the tubular plasma cell 200. Air C from the surrounding environment (i.e. a room or chamber to be decontaminated) is introduced via a separate inlet 240 and propelled into the dielectric space by fan 245.
The control of the relative speeds of the fans 222, 245 enables the control and adjustment of the population of de-ionised water droplets in the dielectric space.
FIGS. 4 to 6 of the accompanying drawings illustrate an alternative plasma cell 300, and an array of such cells 400, according another aspect of the present invention. Each plasma cell 300 of an array 400 is columnar and has a central high-voltage, high-frequency electrode 302 surrounded by a dielectric of activated alumina pellets 304, typically 5-6 mm in diameter. The activated alumina pellets are held in position relative to the central anode by means of a cathode mesh 306, of a size suitable to retain the pellets. When a suitable power supply 315, typically 10 Kv at 20 KHz is applied to the electrodes, a non-thermal plasma is created in the dielectric 304 between the anode 302 and cathode 306. It has been demonstrated by experimentation that the effective non-thermal plasma field 308 (illustrated by broken lines in FIGS. 4 and 5) extends some way beyond the physical size of the cell, probably due to electrons freed by the energy created within the cell.
The arrangement of the individual columnar cells in staggered rows, as shown in FIG. 4, makes use of the “extended” plasma field 308 to treat air (represented by the arrows in FIG. 4) that is directed through the array whilst minimising back pressure within the decontamination system. Again, this provides a more efficient and economical device. Each outer wall of the array is provided with insulation, for example in the form of a laminated structure 310, for example of silicone rubber, as shown in FIG. 5.
Additionally, baffles 312 are provided on the internal the wall of the array 400 and between rows of the cells to guide air between the individual plasma cells 300. The plasma fields 308 touch or overlap (depending upon the spacing of the cells and field applied) and thus the air cannot pass through the array without entering a plasma state. The physical control of the air directs the air stream at the plasma columns, ensuring larger particles and molecules are adsorbed partially on to the dielectric material 304, allowing a longer exposure to the plasma field 308, and the inherent oxidative action, that acts to destroy these larger contaminants.
The individual cells making up the array may be sequentially switched at a frequency sufficient to maintain a non-thermal plasma in the individual cells, even though the power supplying that cell is momentarily absent. This relies on the observation that a pulsed non-thermal plasma state exists for several hundredths of second longer than the pulse of electrical energy required to create it. Such sequential switching may be obtained by using proprietary automotive distribution technology, electro-mechanical or solid-state.
The embodiments described above are given by way of example only, and modifications will be apparent to persons skilled in the art without departing from the scope of the invention as defined by the appended claims.

Claims (7)

The invention claimed is:
1. An apparatus for decontamination of air, the apparatus comprising:
a housing having an air inlet and an air outlet with an air passage therebetween;
an arrangement adapted to direct a stream of air through the housing; and
a non-thermal plasma cell, an ultraviolet (UV) emitting device and an ozone depletion catalyst all included in the housing, the non-thermal plasma cell comprising an anode, a dielectric and a cathode, the cathode being a meshed enclosure which surrounds the ultraviolet emitting device and ozone depletion catalyst to form a reaction chamber and Faraday cage,
wherein the dielectric comprises deionized water droplets or vapor.
2. An apparatus for decontamination of air, the apparatus comprising:
a housing having an air inlet and an air outlet with an air passage therebetween;
an arrangement adapted to direct a stream of air through the housing;
a non-thermal plasma cell, an ultraviolet (UV) emitting device and an ozone depletion catalyst all included in the housing, the non-thermal plasma cell comprising an anode, a dielectric and a cathode, the cathode being a meshed enclosure which surrounds the ultraviolet emitting device and ozone depletion catalyst to form a reaction chamber and Faraday cage; and
a water droplet emitter provided within the housing to deliver a fine spray of water into the reaction chamber.
3. An apparatus for decontamination of air, the apparatus comprising:
a housing having an air inlet and an air outlet with an air passage therebetween,
an arrangement adapted to direct a stream of air through the housing, and
a non-thermal plasma cell, an ultraviolet (UV) emitting device and an ozone depletion catalyst all included in the housing, the non-thermal plasma cell comprising an anode, a dielectric and a cathode, the cathode being a meshed enclosure which surrounds the ultraviolet emitting device and ozone depletion catalyst to form a reaction chamber and Faraday cage,
wherein the housing includes an arrangement adapted to deliver microwaves of a certain wavelength to the reaction chamber.
4. The apparatus of claim 3 further comprising a hydrocarbon emitter provided within the housing downstream of the reaction chamber.
5. The apparatus of claim 3 wherein the cathode comprises a porous mesh of conducting material that is formed into a cage-like structure for surrounding the UV emitting device and ozone depletion catalyst.
6. The apparatus of claim 3 wherein the ozone depletion catalyst surrounds the UV emitting device.
7. An apparatus for decontamination of air, the apparatus comprising:
a housing having an air inlet and an air outlet with an air passage therebetween;
an arrangement adapted to direct a stream of air through the housing; and
a non-thermal plasma cell, an ultraviolet (UV) emitting device and an ozone depletion catalyst all included in the housing, the non-thermal plasma cell comprising an anode, a dielectric and a cathode, the cathode being a meshed enclosure which surrounds the ultraviolet emitting device and ozone depletion catalyst to form a reaction chamber and Faraday cage,
wherein the cathode houses a microwave emitter for delivering microwaves of a certain wavelength to excite the UV emitting device.
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Cited By (7)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
RU174109U1 (en) * 2017-01-27 2017-10-02 Общество с ограниченной ответственностью "Ферропласт-Медикал" BACTERICIDAL INSTALLATION FOR DISINFECTION OF AIR IN PREMISES IN THE PRESENCE OF PEOPLE
US9919939B2 (en) 2011-12-06 2018-03-20 Delta Faucet Company Ozone distribution in a faucet
US10456736B2 (en) 2015-10-19 2019-10-29 Paloza Llc Method and apparatus for purification and treatment of air
US11103881B2 (en) * 2018-08-02 2021-08-31 Faurecia Interior Systems, Inc. Air vent
WO2021244981A1 (en) * 2020-06-01 2021-12-09 Creo Medical Limited Sterilisation apparatus for producing plasma and hydroxyl radicals
US20220154953A1 (en) * 2020-11-19 2022-05-19 Icon Integrated Concepts Llc Air purifier systems and methods
US11458214B2 (en) 2015-12-21 2022-10-04 Delta Faucet Company Fluid delivery system including a disinfectant device

Families Citing this family (61)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JP5891609B2 (en) * 2011-05-30 2016-03-23 株式会社明電舎 Passivation method
GB2496888A (en) * 2011-11-25 2013-05-29 Tri Air Developments Ltd Non-thermal plasma cell
FR2983471B1 (en) * 2011-12-01 2017-03-10 Beewair PROCESS FOR TREATING EFFLUENTS IN A BED OF MICROBALLS BY COLD PLASMA AND PHOTOCATALYSIS
US10265432B2 (en) 2012-01-17 2019-04-23 Dbg Group Investments, Llc Equipment for sanitizing the air conditioning system of vehicles by means of radiant catalytic ionization
BR102012001122B1 (en) * 2012-01-17 2021-09-08 Ecoquest Do Brasil - Com, Impor, Expor E Serv Para Purif De Ar E Ág EQUIPMENT FOR SANITIZING THE VEHICLE AIR CONDITIONING SYSTEM USING CATALYTIC RADIANT IONIZATION
WO2013185568A1 (en) * 2012-06-11 2013-12-19 Liu Yigang Ionic purification device, and frequency modulation method and system of transformer
CN102861493B (en) * 2012-09-12 2014-05-28 广东森洋环境保护工程设备有限公司 Photoelectric high-energy purification device for treating particulate matter 2.5 (PM2.5) in cooking fume
BG66690B1 (en) * 2012-11-12 2018-06-29 Христо Ковачки Plasma electrochemical flue gas purification method
CN102961771A (en) * 2012-11-28 2013-03-13 华南理工大学 Plasma air disinfection device
FR3001641B1 (en) * 2013-02-01 2015-02-27 Ciat Sa DEVICE, SYSTEM AND METHOD FOR TREATING GAS
DE202013001963U1 (en) * 2013-02-27 2013-05-02 Al-Ko Kober Ag Room air cleaner
CN103245010B (en) * 2013-05-14 2016-08-17 广东国得科技发展有限公司 A kind of air filtering disinfection eliminates the device of harmful gas
US20160151530A1 (en) * 2013-07-31 2016-06-02 Hitachi, Ltd. Sanitization Device Using Electrical Discharge
GB201402624D0 (en) * 2014-02-14 2014-04-02 Tri Air Developments Ltd Air decontamination device and method
GB2524008A (en) * 2014-03-10 2015-09-16 Novaerus Patents Ltd Air disinfection and pollution removal method and apparatus
US20150343109A1 (en) 2014-04-03 2015-12-03 Novaerus Patent Limited Coil Assembly for Plasma Generation
EP2937633A1 (en) * 2014-04-22 2015-10-28 E.G.O. ELEKTRO-GERÄTEBAU GmbH Device for purifying air, ventilation device and method of air purification
GB2526627A (en) 2014-05-30 2015-12-02 Novaerus Patents Ltd A plasma coil electrostatic precipitator assembly for air disinfection and pollution control
EP3162435B1 (en) * 2014-06-27 2020-03-11 Kyushu Institute of Technology Method for manufacturing reaction product in which phase interface reaction is employed and phase interface reactor
GB2533466A (en) * 2015-10-22 2016-06-22 Darwin Tech Int Ltd Air cleaning device
ITUB20155040A1 (en) * 2015-10-23 2017-04-23 Irca Spa Device for purifying exhaust gases from endothermic engines
US10980911B2 (en) 2016-01-21 2021-04-20 Global Plasma Solutions, Inc. Flexible ion generator device
JP6535141B2 (en) 2016-03-22 2019-06-26 コーニンクレッカ フィリップス エヌ ヴェKoninklijke Philips N.V. Low temperature plasma apparatus for treating a surface
US11695259B2 (en) 2016-08-08 2023-07-04 Global Plasma Solutions, Inc. Modular ion generator device
US11283245B2 (en) 2016-08-08 2022-03-22 Global Plasma Solutions, Inc. Modular ion generator device
CN106422690A (en) * 2016-08-25 2017-02-22 北京航天环境工程有限公司 Organic waste gas plasma processing device
WO2018071211A1 (en) * 2016-09-30 2018-04-19 Plasmanano Corporation Plasma surface decontamination: method and apparatus for reducing radioactive nuclear waste and toxic waste volume
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WO2018093407A1 (en) * 2016-11-21 2018-05-24 Inventure Labs Llc An automated modular environment modification device
CN106731589B (en) * 2017-01-09 2019-09-06 深圳市创海森环保科技有限公司 A kind of hydroxyl radical free radical generating system
RU178660U1 (en) * 2017-02-27 2018-04-16 Общество С Ограниченной Ответственностью "Овис" Device for cleaning and regenerating air
ES2692429A1 (en) * 2017-06-02 2018-12-03 Gabriel Edgardo PROCUPETZ SCHEIN DEVICE TO DECONTAMINATE THE AIR IN OUTER SPACES. (Machine-translation by Google Translate, not legally binding)
KR102409911B1 (en) * 2017-06-19 2022-06-16 오와이 리파 에어 엘티디 electric filter structure
CN107321148A (en) * 2017-07-14 2017-11-07 四川大学 A kind of VOCs for removing low concentration big flow method and its modified catalyst
JP6971717B2 (en) * 2017-08-30 2021-11-24 荏原実業株式会社 Phase interface reaction device, plant cultivation device and reaction product production method
CN108260269A (en) * 2017-12-25 2018-07-06 罗璐 Low temperature plasma generating device and gas handling system
JP7169371B2 (en) 2018-02-12 2022-11-10 グローバル プラズマ ソリューションズ,インコーポレイテッド Self-cleaning ion generator
RU181535U1 (en) * 2018-03-21 2018-07-17 Общество С Ограниченной Ответственностью "Овис" Device for cleaning and regenerating air
RU188176U1 (en) * 2018-03-21 2019-04-02 Общество С Ограниченной Ответственностью "Овис" Device for cleaning and regenerating air
RU182793U1 (en) * 2018-03-21 2018-09-03 Общество С Ограниченной Ответственностью "Овис" Device for cleaning and regenerating air
CN108392981A (en) * 2018-05-08 2018-08-14 陕西青朗万城环保科技有限公司 A kind of ozone abater
FR3083120A1 (en) * 2018-07-02 2020-01-03 Cp2N AIR PURIFICATION SYSTEM BY CONTROLLED HUMIDIFICATION AND IONIZATION, AND AERAULIC CIRCUIT EQUIPPED WITH SUCH A SYSTEM.
US11246955B2 (en) * 2018-10-29 2022-02-15 Phoenixaire, Llc Method and system for generating non-thermal plasma
US11581709B2 (en) 2019-06-07 2023-02-14 Global Plasma Solutions, Inc. Self-cleaning ion generator device
RU2742273C1 (en) * 2019-12-03 2021-02-04 Общество с ограниченной ответственностью Производственная компания "Лаборатория импульсной техники" Method and device for cleaning air of harmful and odorous substances, uv-lamp and unit of sorption-catalytic backfill for implementation thereof
CN113134289A (en) * 2020-01-20 2021-07-20 江阴挪能材料科技有限公司 Method for purifying air and air purification device
DE102020101540B4 (en) 2020-01-23 2023-12-14 Kunststoff Helmbrechts Ag Process for exhaust air purification, as well as plasma module, agglomeration module and UV treatment module for use in such a process
EP3858466A1 (en) * 2020-01-28 2021-08-04 Samsung Electronics Co., Ltd. Device and method for purifying air
GB2594500A (en) * 2020-04-30 2021-11-03 Creo Medical Ltd Sterilisation apparatus for producing plasma and hydroxyl radicals
US20230232870A1 (en) * 2020-05-29 2023-07-27 Aa Plasma Llc Food and fresh produce disinfection chamber utilizing fast mixed liquid and nonequilibrium plasma-generated species
FR3111569A1 (en) * 2020-06-22 2021-12-24 Alain HILAIRE Apparatus for treating the air and the interior surfaces of a room comprising a turbine and a reservoir of decontaminating liquid composition for mixing with the air to be treated sucked in by the turbine.
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EP4005667A1 (en) * 2020-11-27 2022-06-01 Plasma Innova S.A. Non-thermal plasma air purifier
RU203298U1 (en) * 2020-12-22 2021-03-30 Александр Михайлович Панин Air purifier
CN113294865B (en) * 2021-05-26 2021-12-21 江苏弗瑞仕环保科技有限公司 Long-life plasma disinfection module and air environmental protection disinfecting equipment
EP4348124A1 (en) * 2021-05-27 2024-04-10 Petra Sprenger Disinfection unit
CN113274876A (en) * 2021-06-28 2021-08-20 江苏博恩环境工程成套设备有限公司 Double-microwave coupling waste gas treatment system
CN113441278B (en) * 2021-06-30 2022-11-18 佛山市顺德区诚芯环境科技有限公司 Particulate matter collecting structure and electrostatic dust collection device
AU2021221402A1 (en) * 2021-07-06 2023-02-02 HQ Air Limited Method and apparatus for the generation of hydroxyl radicals
KR102390224B1 (en) * 2021-08-02 2022-04-25 안종한 Air purification sterilizer with cnt electrodes
ES2930587B2 (en) * 2022-04-28 2023-09-18 I Mas Jordi Benseny MEANS FOR ELECTRICAL STABILIZATION OF THE REACTION CHAMBER IN HYDROXYL RADICAL GENERATION SYSTEMS

Citations (19)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
DE3515508C1 (en) 1985-04-30 1986-10-30 Karl 7031 Steinenbronn Grob Apparatus for purifying the air in living rooms and activity rooms, in particular kitchens
WO1999012637A1 (en) 1997-09-09 1999-03-18 Aea Technology Plc Substrate media for plasma gas processing reactors
US5961920A (en) * 1994-12-28 1999-10-05 Benrad Aktiebolag Method and apparatus for treatment of fluids
US5993738A (en) * 1997-05-13 1999-11-30 Universal Air Technology Electrostatic photocatalytic air disinfection
US6500387B1 (en) * 2000-05-19 2002-12-31 Nukuest, Inc. Air actinism chamber apparatus and method
US6589489B2 (en) * 2001-03-30 2003-07-08 L2B Environmental Systems Inc. Air purifier
US6620385B2 (en) * 1996-08-20 2003-09-16 Ebara Corporation Method and apparatus for purifying a gas containing contaminants
WO2006003382A1 (en) * 2004-06-30 2006-01-12 Tri-Air Developments Limited Air decontamination device and method
US20060188387A1 (en) * 2003-06-16 2006-08-24 University Of Florida Research Foundation, Inc. Photoelectrochemical air disinfection
US20070020159A1 (en) 2005-07-20 2007-01-25 Tsui Herman Y W Apparatus for air purification and disinfection
WO2007051912A1 (en) 2005-11-07 2007-05-10 Ahlstrom Corporation Combined treatment of gaseous effluents by cold plasma and photocatalysis
US20070137486A1 (en) 2005-12-17 2007-06-21 Airinspace Limited Electrostatic filter
US20070217944A1 (en) * 2003-01-06 2007-09-20 The Johns Hopkins University Hydroxyl free radical-induced decontamination of airborne spores, viruses and bacteria in a dynamic system
US20070253860A1 (en) * 2004-10-18 2007-11-01 Werner Schroder Process and device for sterilising ambient air
US20080170971A1 (en) 2006-08-09 2008-07-17 Airinspace B.V. Air purification devices
WO2009002295A1 (en) 2007-06-22 2008-12-31 Carrier Corporation Purification of a fluid using ozone with an adsorbent and/or a particle filter
EP2019464A1 (en) 2006-05-19 2009-01-28 Daikin Industries, Ltd. Discharge device and air purifying device
JP2009519819A (en) 2005-12-17 2009-05-21 エアーインスペース・ビー.ブイ. Air purification device
US20100178196A1 (en) * 2007-02-22 2010-07-15 Christopher John Garner Sterilizer

Family Cites Families (10)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
FR2790962B1 (en) * 1999-03-16 2003-10-10 Absys PLASMA STERILIZATION PROCESS AND DEVICES
TW518686B (en) * 1999-12-29 2003-01-21 Tokyo Electron Ltd System for automatic control of the wall bombardment to control wall deposition
EP1432455A1 (en) * 2001-10-04 2004-06-30 The Johns Hopkins University Airborne pathogen neutralization
JP3889280B2 (en) * 2002-01-07 2007-03-07 忠弘 大見 Plasma processing equipment
TWI264313B (en) * 2002-08-07 2006-10-21 Access Business Group Int Llc Nonthermal plasma air treatment system
JP4457603B2 (en) * 2002-08-09 2010-04-28 三菱電機株式会社 Gas purification device
JP2004337345A (en) * 2003-05-15 2004-12-02 Ngk Insulators Ltd Deodorizing apparatus and deodorizing method
JPWO2004112940A1 (en) * 2003-06-17 2006-07-27 日鉄鉱業株式会社 Gas processing method and gas processing apparatus using oxidation catalyst and low-temperature plasma
FR2856600B1 (en) * 2003-06-27 2005-09-02 Satelec Soc DEVICE AND METHOD FOR POST-DISCHARGE PLASMA STERELIZATION
JP4785669B2 (en) * 2006-08-04 2011-10-05 シャープ株式会社 Pollutant gas purification apparatus and pollutant gas purification method

Patent Citations (23)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
DE3515508C1 (en) 1985-04-30 1986-10-30 Karl 7031 Steinenbronn Grob Apparatus for purifying the air in living rooms and activity rooms, in particular kitchens
US5961920A (en) * 1994-12-28 1999-10-05 Benrad Aktiebolag Method and apparatus for treatment of fluids
US6358478B1 (en) * 1994-12-28 2002-03-19 Benrad Aktiebolag Method and apparatus for treatment of fluids
US6620385B2 (en) * 1996-08-20 2003-09-16 Ebara Corporation Method and apparatus for purifying a gas containing contaminants
US5993738A (en) * 1997-05-13 1999-11-30 Universal Air Technology Electrostatic photocatalytic air disinfection
WO1999012637A1 (en) 1997-09-09 1999-03-18 Aea Technology Plc Substrate media for plasma gas processing reactors
US6500387B1 (en) * 2000-05-19 2002-12-31 Nukuest, Inc. Air actinism chamber apparatus and method
US6589489B2 (en) * 2001-03-30 2003-07-08 L2B Environmental Systems Inc. Air purifier
US20070217944A1 (en) * 2003-01-06 2007-09-20 The Johns Hopkins University Hydroxyl free radical-induced decontamination of airborne spores, viruses and bacteria in a dynamic system
US20060188387A1 (en) * 2003-06-16 2006-08-24 University Of Florida Research Foundation, Inc. Photoelectrochemical air disinfection
WO2006003382A1 (en) * 2004-06-30 2006-01-12 Tri-Air Developments Limited Air decontamination device and method
US20080193326A1 (en) * 2004-06-30 2008-08-14 Alan Mole Air Decontamination Device and Method
JP2008504094A (en) 2004-06-30 2008-02-14 トゥリ−エアー ディベロップメンツ リミテッド Air decontamination equipment and method
EP1799330A1 (en) 2004-06-30 2007-06-27 Tri-Air Developments Limited Air decontamination device and method
US20070253860A1 (en) * 2004-10-18 2007-11-01 Werner Schroder Process and device for sterilising ambient air
US20070020159A1 (en) 2005-07-20 2007-01-25 Tsui Herman Y W Apparatus for air purification and disinfection
WO2007051912A1 (en) 2005-11-07 2007-05-10 Ahlstrom Corporation Combined treatment of gaseous effluents by cold plasma and photocatalysis
US20070137486A1 (en) 2005-12-17 2007-06-21 Airinspace Limited Electrostatic filter
JP2009519819A (en) 2005-12-17 2009-05-21 エアーインスペース・ビー.ブイ. Air purification device
EP2019464A1 (en) 2006-05-19 2009-01-28 Daikin Industries, Ltd. Discharge device and air purifying device
US20080170971A1 (en) 2006-08-09 2008-07-17 Airinspace B.V. Air purification devices
US20100178196A1 (en) * 2007-02-22 2010-07-15 Christopher John Garner Sterilizer
WO2009002295A1 (en) 2007-06-22 2008-12-31 Carrier Corporation Purification of a fluid using ozone with an adsorbent and/or a particle filter

Non-Patent Citations (3)

* Cited by examiner, † Cited by third party
Title
Great Britain Search Report for Application No. GB0904978.4, dated Jul. 23, 2009.
Notification of Reasons for Rejection for Application No. 2012-501365, mailed Aug. 6, 2013.
Search Report for International Patent Application No. PCT/GB2010/000346; Jul. 19, 2010.

Cited By (8)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US9919939B2 (en) 2011-12-06 2018-03-20 Delta Faucet Company Ozone distribution in a faucet
US10947138B2 (en) 2011-12-06 2021-03-16 Delta Faucet Company Ozone distribution in a faucet
US10456736B2 (en) 2015-10-19 2019-10-29 Paloza Llc Method and apparatus for purification and treatment of air
US11458214B2 (en) 2015-12-21 2022-10-04 Delta Faucet Company Fluid delivery system including a disinfectant device
RU174109U1 (en) * 2017-01-27 2017-10-02 Общество с ограниченной ответственностью "Ферропласт-Медикал" BACTERICIDAL INSTALLATION FOR DISINFECTION OF AIR IN PREMISES IN THE PRESENCE OF PEOPLE
US11103881B2 (en) * 2018-08-02 2021-08-31 Faurecia Interior Systems, Inc. Air vent
WO2021244981A1 (en) * 2020-06-01 2021-12-09 Creo Medical Limited Sterilisation apparatus for producing plasma and hydroxyl radicals
US20220154953A1 (en) * 2020-11-19 2022-05-19 Icon Integrated Concepts Llc Air purifier systems and methods

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